Circuit breaker



Dec. 15, 1959 R. c. VAN SICKLE CIRCUIT BREAKER 3 Sheets-Sheet 1 Filed Dec. 50, 1957 Fig.7.

INVENTOR Roswell C. VonSickIe WITNESSES Dec. 15, 1959 R. c. VAN SICKLE 2,917,602

CIRCUIT BREAKER Filed Dec. 30. 1957 5 Sheets-Sheet 2 x s 2O R. C. VAN SICKLE Dec. 15, 1959 I CIRCUIT BREAKER 3 Sheets-Sheet 3 Filed Dec.- 30. 1957 States Patent 2,917,602 CIRCUIT BREAKER Roswell C. Van Sickle, Wilkinsburg, Pa., assignor to Westinghouse Electric Corporation, East Pittsburgh, Pa., a corporation of Pennsylvania Application December 30, 1957, Serial No. 706,213 Claims. (Cl. 200106) This invention relates to circuit breakers and more particularly to circuit breakers operated by fluid pressure.

-An object of the invention is to provide a circuit breaker having trip-free and non-trip-free tripping means with holding electromagnets which are selectively saturated to determine the tripping means to be operated.

Another object of the invention is to provide a circuit breaker having trip-free and non-trip-free tripping means with a holding magnet for each tripping means and selecting means for selecting which of the holding magnets is to be operated.

Another object of the invention is to provide a circuit breaker having power operated closing means and tripfree and non-trip-free tripping means including a holding magnet for each of the tripping means, each of said magnets being provided with an armature, with selector means responsive to the energized condition of the closing means to selectively determine which of the holding magnets is to release its armature to effect tripping of the breaker.

Another object of the invention is to provide a circuit breaker having power operated closing means and a tripfree tripping means and a non-trip-free tripping means, each of said tripping means being provided with a holding magnet having a portion saturable in response to a tripping impulse for holding the tripping means in operating position, and selector means responsive to the energized condition to selectively determine which of the holding magnets is to function to release its associated tripping means. I

Another object of the invention is to provide a circuit breaker with an improved trip device having a holding inagnet including an armature, yoke members and a coil energized in response to overload currents, said yoke members having portions saturable in response to energi- Zation of the coil to effect release of the armature and tripping of the breaker.

The invention both as to structure and operation, together with additional objects and advantages thereof, will be best understood from the following detailed description thereof when read in conjunction with the accompanying drawings:

Figure l'is aside-elevational view of a circuit breaker embodying the principles of the invention;

Fig. 2 is a vertical sectional view taken substantially on line lill of Fig. 1 and looking in the direction of the arrows;

Pig. 3 is a vertical sectional view taken on line IIIl-ll of Fig. 1 showing the valve mechanism for controlling the admission of fluid pressure to the operating cylinders;

Fig. 4 is an elevational view partly in section showing a modification of the invention applied to a circuit breaker which embodies 'a trip-free tripping mechanism only.

'Figs. 5 and 6 illustrate a modification of the holding magnet means, Fig. 6 being a sectional view taken on line VI-Vl of Fig. 5.

Fig. 7 is a detail view showing a modification of the trip magnet selecting device.

The invention is illustrated as applied to a circuit breaker of the type fully disclosed in R. C. Van Sickle Patent No. 2,656,430 issued October 20, 1953.

Referring to Fig. 2 of the drawing, the circuit breaker 11, which is illustrated diagrammatically, may be of any conventional construction and is adapted to be operated to the open positions by means of an accelerating spring 3.3. The circuit breaker is adapted to be operated to the closed position by means of an operating mechanism which in the embodiment shown is of the compressed fluid type. The operating mechanism includes an operating cylinder 17 closed at its upper end by a plate 19 and at its lower end by a bottom plate 20 secured together by means of bolts 21 (Fig. 1). Mounted in the operating cylinder 17 (Fig. 2) is an operation piston 23 having secured thereto a piston rod 25 which is slidable through a substantially airtight opening in the plate 19. A coupling 27 rigidly secured to the upper end of the piston rod 25 is releasably connected to a coupling 29 secured to a breaker operating rod 31 by means of an inverted toggle comprising toggle links 33 and 35. The breaker operating rod 31 is operatively connected to the circuit breaker 11 by means of a suitable linkage.

The toggle link 33 comprises a pair of spaced parallel links pivotally connected by means of a pivot pin 37 to the coupling 27. The toggle link 35 comprises a toggle link disposed between the links 33 and is pivotally connected to the coupling 29 by a pivot pin 39. The toggle links 33 and 35 are pivotally connected together by a knee pivot pin 41.

'In order to provide straight-line movement of the operating rod 31 and the piston rod 25 and to assist the tripfree toggle 33-35 in maintaining the breaker closed, the pivot pins 37 and 39 are provided with rollers 43 and 44, respectively, there being a roller 43 mounted on each end of the pin 37 and a roller 44 mounted on each of the pin 39. These rollers cooperate with corresponding vertical slots 45 formed in a pair of spaced frame members 47 rigidly mounted on the plate 19 and extending upwardly therefrom in spaced parallel relation. To form substantial bearing surfaces for the rollers 43 and 44, plates 49 having bearing surfaces coinciding with the slots 45 are suitably secured to the outside of the frame members 47.

The circuit breaker is held in the closed position by a main latch 51 (Fig. 2) and a light-load latch mechanism indicated generally at 53. The main latch 51 is pivotally mounted on a pin 55 supported in the frame members 47 and is biased by means of a spring-pressed plunger 57 into latching engagement with a latch member 59 on the coupling 27. The plunger 57 is slidably mounted on a rod 58 mounted in a cross bar 61 supported between the frame members 47 and is biased by a compression spring 63. The main latch 51 has a latching surface 67 cooperating with the latch 59 on the coupling 27 and also has a projection 69 carrying a latch roller 70 which cooperates with the latch mechanism 53. The non-trip-free latch comprises a latch carrier 78 pivoted on the pin 85 and having a trigger latch 80 of the slip-off type pivotally mounted thereon by means of a pivot pin 81 in an offset portion of the member 78. A spring 82 compressed between the trigger latch 80 and an extension 84 of the member 78 biases the trigger latch 80 to latching position against a shoulder 98 on the member 78. A spring 88 compressed between the cross plate 89 and a spring clip on the pivot 81 biases the non-trip-free latch carrier 78 to latching position.

A generally U-shaped bracket 92 (Figs. 1 and 2) has its side portions rigidly secured to the side members 47 and supports a tripping magnet indicated generally at 91. The magnet 91 is a holding magnet and comprises yoke members 93 having a permanent magnet 94 between the lower portion thereof and normally holds the non-tripfree latch 76 in latching position. A tripping coil 95 is mounted in the yoke members 93 each of which are made in two parts to receive the coil. A movable armature 97 pivotally connected to the non-trip-free latch carrier 78 is normally held against the pole faces of the yoke members 93 by the flux of the permanent magnet 94 to hold the non-trip-free latch 76 in latching position.

Each of the yoke members 93 is provided with a pair of outwardly extending pole pieces 99 adjacent the trip coil 95 and a trip selector 101 of non-magnetic material carries pieces 103 of magnetic material for controlling the flux saturation in the magnet yokes 93 adjacent the coil 95. As seen in Fig. 1, a second tripping magnet, indicated generally at 96, is provided for controlling the trip-free latch 75. The trip-free magnet 96 is the same as the non-trip-free magnet 91 just described except that its armature 97 is pivotally connected to the trip-free latch 75 and normally holds this latch in latching position. The trip selector 101 (Figs. 1 and 2) is U-shaped and the legs thereof extend on opposite sides of the two trip magnets 91 and 96 and are slidably mounted in slots (not shown) in an upwardly extending portion 96 of the bracket 92. As shown in Fig. 1, the magnetic members 103 associated with the non-trip-free tripping magnet 91 are normally offset to the left of the yoke members 93, and the magnetic members 103 associated with the tripfree tripping magnet 96 are in a position adjacent the yoke members 93 for that magnet.

When a tripping impulse occurs the coils 95 of both magnets 91 and 96 are momentarily energized by the tripping impulse. In the position of the magnetic member shown the coil 95 for the non-trip-free magnet 91 will cause flux saturation in the yoke members 93 adjacent this coil 95 and effect release of the armature 97 for the nontrip-free magnet. Since the magnetic members 103 of the trip-free magnet 96 are in position adjacent the pole pieces 99 on the yoke member 93, they form a flux bypass circuit in the area of the coil, and the armature 97 for the tripfree magnet will be held in attracted position as shown and prevent tripping operation of the trip-free latch 75.

At its right-hand end the trip selector 101 is pivotally connected to the upper end of a lever 121 by means of a pin 123. The lever 121 is pivotally supported on a pin 127 in a bracket 125 secured to the adjacent bracket 92 and is biased in a counterclockwise direction to the position shown by a compression spring 135.

The light-load latch mechanism 53 includes an underset tripping toggle comprising toggle links 71 and 73, a trip-free trigger latch 75 of the slip-off type cooperating to releasably maintain the tripping toggle in its underset position, and a non-trip-free latch indicated generally at 76 cooperating with the latch roller 70 on the main latch 51. The toggle link 71 comprises a casting having a pair of side members rigidly joined by a cross member 77 and pivotally on a fixed pivot pin 79 supported in the frame 47. At their free ends the toggle links 71 between them carry a latch roller 81 with which the trigger latch 75 cooperates to maintain the tripping toggle 7173 in its underset position. The toggle link '73 is pivotally connected on the knee pivot pin 41 of the trip-free toggle 33-35 and is pivotally connected to the toggle link 71 by a knee pivot pin 83.

The trip-free latch 75 and the non-trip-free latch car rier 78 are pivoted on a pin 85 supported in a pair of brackets 86 and 87 (Fig. 1) which are secured to a cross plate 89 mounted on the frame members 47. When the selector bar 101 is shifted to the right (Fig. 1) by means and under conditions to be described hereinafter, the magnetic member 103 of the trip-free bracket 96 will be moved away from the yokes of the trip-free magnet, and the magnetic pieces for the non-trip-free magnet will be positioned adjacent the yokes 93 of the non-trip-free magnet 91. Consequently, when a tripping impulse is received with the selector bar 101 in this position, it will cause release of the trip-free latch and trip the breaker free of the closing means, while the non-trip-free magnet 31 is prevented from releasing its armature 97.

Referring to Fig. 2 of the drawing, in the closed position of the breaker, the latch 51, which is held in latching position by the non-trip-free latch 76, holds the piston 23 in the closed position in which it is shown against the force exerted by the accelerating spring 13 and the force of a spring 147 (Fig. 2) compressed between the bottom of the piston 23 and a disc 149. The disc 149 is suitably secured to a cylindrical member 151 which has secured thereto a ring 153 supported on'certain of the bolts 21 that fasten the bottom plate 20 of the operating cylinder in place. The latch 51 is of the slip-01f type, that is, the latch 51 is so constructed and arranged with respect to the latch member 59 that it will not itself hold the piston rod 25 in the closed position against the biasing force of the spring 147. The relative positions of the parts are such that the upward thrust of the springs 13 and 147 applies a small component of the force through the latch roller 70 to the non-trip-free latch 76.

The accelerating spring 13 applies an upward force on the breaker operating rod 31, and, since the pivot pins 37 and 39 are constrained by the slots 45 to move in a straight line, a small component of the force of the spring 13 is applied through the link 35 to the tripping toggle 7173. Due to the tripping toggle being only slightly underset, a very small component of the force of the accelerating spring 13 is applied through the tripping toggle 71-73 and the latch roller 81 to the tript'ree latch 75 which is restrained in latching position by its holding armature 97.

Assuming the breaker to be in the closed position, it is tripped open by the non-trip-free latch means in the following manner:

When the tripping magnets 91 and 96 are energized from a suitable source, the armature 97 for the non trip-free magnet 91 is released and the force applied to the latch by the latch 51 moves the non-trip-free latch 89 and the non-trip-free latch carrier 78 counterclockwise (Fig. 2) to unlatching position. This frees the latch 51 and the accelerating spring 13, moves the latch 51 to unlatching position and operates the breaker to open position. While the roller 70 holds the latch 80 down until the breaker is closed, the spring 88 immediately resets the non-trip-free latch carrier 78. During the non-trip-free opening movement, the main toggle 33-35 is held in thrust transmitting position by the toggle link 73 which, due to the fact that the toggle link 71 is held in the position shown, moves clockwise about the pin 83 as a fixed pivot. The result is that the breaker operating rod 31 and the piston rod 25 move upwardly as a unit, the breaker going to the open position and the piston 23 being moved to the upper end of the cylinder 17.

The circuit breaker is closed by admitting compressed fluid to the operating cylinder 17 above the piston 23 which forces the piston downwardly, drawing the toggle link 33 therewith. Since the toggle link 71 of the tripping toggle is held in the position shown in Fig. 2 by the trip-free latch 75, the link 73 again pivots about the pivot pin 83 which acts as a fixed pivot, thereby holding the main toggle 3335 in thrust transmitting position during the closing operation. The closing force applied to the link 33 is, therefore, transmitted through the link 35 to move the breaker rod 31 downwardly and close the breaker.

Under certain conditions, to be described later, the lever 121 (Fig. 1) is rotated clockwise about its pivot and draws the latch selector bar 101 to the right. This moves the magnetic pieces 103 to the right positioning the pieces 103 for the non-trip-free magnet 91 adjacent thereto and moves the pieces 103 for the trip-free magnet away from the yoke members. Energization of the coils 95 now causes the trip-free magnet 96 to release its armature 97 and the force applied by the roller 81 to the trip-free latch moves the trip-free latch 75 to unlatching position. This releases the underset tripping toggle 71-73 and the force of the accelerating spring 13 applied to the tripping toggle causes collapse of this toggle and permits collapse of the main toggle 33-35. When this occurs the breaker operating rod 31 moves upwardly free of the piston 23 to open the breaker free of the closing means.

In order to restore the main toggle 33-35 to thrust transmitting position to thereby recouple the breaker to the closing means, it is necessary to release the latch 51 which permits the spring 147 to move the piston 23 and the .piston rod upwardly. This is effected by a projection 155 on the trip-free latch 75 which, after a predetermined movement of the trip-free latch in unlatching direction, engages and moves the non-trip-free latch 80 to its unlatching position. The spring 147 now forces the latch 51 to unlatching position and moves the piston 23 and the piston rod 25 upwardly. The pivots 37 and 39 being constrained to travel in a straight line by the slots 45, the upward movement of the toggle link 33 will cause the link 35 to rotate counterclockwise about the pivot 39 to the normal inverted or thrust transmitting position of the toggle 33-35. This action, through the knee pin 41 and the line 73 moves the link 71 about its pivot 79 far enough to permit reengagement of the trip-free latch 75 under the latch roller 81 and resets the holding magnet armature. This restores the main toggle to thrust transmitting position thereby recoupling the piston rod 55 to the breaker operating rod 31 in preparation for a closing operation.

Compressed gas is admitted to the cylinder to close the circuit breaker by means of an inlet valve device indicated generally at 161 (Figs. 1 and 3). The inlet valve device comprises a main housing 163 secured by bolts 165 to the top of the upper plate 19, which closes the upper end of the cylinder. The housing 163 has a cylinder 167 formed therein which is closed at its upper end by a member 168 secured thereto by bolts 185 and in which is disposed a valve operating piston 169. A valve rod 171 having a valve element 173 secured to its lower end extends upwardly through a guide bearing 175 into the cylinder 167 and cooperates with the piston 169. The valve element 173 is secured to the rod 171 by a nut 177 and the valve is biased to closed position by a spring 179 compressed between a closure plate 181 and the valve element 173.

A high-pressure chamber 187 in the housing 163 below the valve 173 is supplied with fluid under pressure from a suitable source by means of a pipe 189. An inlet port 191 above the valve 173 communicates with the operating cylinder. The inlet valve 173 is operated to open position by admitting fluid pressure from the highpressure chamber 187 to the cylinder 167 above the piston 169 which forces the piston downwardly in the cylinder 167 and moves the valve 173 to the open position.

Fluid pressure is admitted to the cylinder 167 by means of a magnetically operated pilot valve device indicated generally at 195 (Figs. 1 and 3). The pilot valve device comprises a housing 197 secured to the housing 163 of the inlet valve device. The housing 197 is provided with a chamber 201 communicating with the highpressure chamber 187. A valve-203 normally closes off the chamber 201 from a passage 205 communicating with the cylinder 167 above the piston 169. The valve 203is biased to the closed position by a spring and is secured on a rod 207 which is attached to the armature (not shown) of an electromagnet 209. Also attached to the rod 207 is a normally open exhaust valve 211 which closes upon opening of the valve 203 to close a passage communicating the passage 205 to atmosphere.

Formed in the housing 163 is a cylinder 213 in which is disposed a cup-shaped exhaust valve 215 for controlling a large exhaust port 217. The valve 215 has a reduced portion 219 disposed in a cylinder 221 which communicates by means of a passage 223 with the cylinder 167 and the passage 205. The cylinder 213 above the valve 215 is normally at atmospheric pressure by means of one or more holes in the valve. The exhaust valve 215 is normally biased by gravity or a suitable spring (not shown) to the closed position where it is seated on a beveled annular valve seat 225 secured to the housing 163 by means of a flange and bolts 227. A chamber 229 surrounding the valve seat 225 and the lower portion of the valve 215 communicates with the cylinder 17 by suitable large passage means (not shown).

When the electromagnet 209 is energized, the rod 207 is moved downwardly closing the exhaust valve 211 and opening the valve 203, thereby admitting fluid pressure from the high-pressure chamber 187 through the. passage 205 to the cylinder 167 above the piston 169. The fluid pressure forces the piston 169 down moving the rod 171 and the inlet valve 173 to open position thereby admitting fluid under pressure through the inlet port 191 to the operating cylinder 17 to close the breaker in the previously described manner.

At the same time the compressed fluid is admitted to the cylinder 167 to open the inlet valve 173, fluid pressure is also admitted through the passage 223 to the cylinder 221 above the piston 219 of the exhaust valve 215 in order to maintain the exhaust valve closed during the closing operation.

When the electromagnet 209 is deenergized at the end of the closing operation, the valve 203 closes and the valve 211 opens to vent the high-pressure fluid from the cylinder 167 to permit the spring 179 to close the inlet valve 173. At the same time, the high-pressure fluid is vented fro-m the cylinder 221 through the passages 223 and 205 whereupon the closing charge of high-pressure fluid in the operating cylinder 17 and in the chamber 229 blasts the exhaust valve 215 open to dump the compressed fluid from the operating cylinder. As soon as the closing charge of compressed fluid is exhausted from the operating cylinder, the exhaust valve 215 is restored to its closed position.

When the breaker arrives at its fully closed position, the spring 63 (Fig. 2) moves the latch 51 into engagement with the latch member 59 on the coupling 27 and the latch engages the roller 70 to hold the mechanism and the breaker in the closed position.

If there is no fault condition such as an overload or a short-circuit current in the main circuit at the time the contacts are closed, the circuit breaker will be latched in the closed position. However, if the breaker closes in against a fault current, the trip magnet 96 will function and trip the breaker free of the closing means by actuating the trip-free latch 75.

It was set forth previously that under certain conditions the lever 121 (Fig. l) is rotated clockwise from the position shown to withdraw the magnetic pieces 103 from trip-free magnet 46 and positions the magnetic pieces 103 from the trip-free magnet 196 adjacent the non-tripfree magnet 91 in order to effect trip-free tripping of the breaker. This is effected by asrnall cyliner 233 (Figs. 1 and 3) in the valve housing 163 and a piston 235 disposed for movement therein. A passage 237 (Fig. 3) communicates the cylinder back of the piston 235 with the inlet port 191. A rod 239 attached to the piston 235 extends out through an opening in a nipple 241 in the end of the cylinder 233. The outer end of the rod 239 is disposed adjacent the lower end of the lever 121 and the spring which normally maintains the lever 121 and the selector bar 101 in the position shown also acts through the lever 121 and rod 239 to hold the piston at the inner end of the cylinder 233.

When the inlet valve 173 is operated to admit fluid pressure through the inlet port 191 to the operating cylinder to close the breaker, fluid pressure is admitted through the passage 237 (Fig. 3) to the cylinder 233 and moves the piston 235 toward the left (Fig. 1). This movement of the piston 235 thrusts the rod 239 outwardly and rotates the lever 121 clockwise to position the latch selector bar 101 for effecting operation of the trip-free magnet 96 as previously set forth. In this manner, the trip-free latch is selected Whenever the breaker closes aga'nst a fault condition with the charge of high-pressure fluid in the operating cylinder 17.

When the inlet valve 173 closes and the exhaust valve 215 opens to dump the closing air from the operating cylinder, the bias of the spring 135 restores the lever 121 and the selector bar 101 to the position shown and moves the piston 235 to the inner end of the cylinder 233.

Figure 4 illustrates a modification of the trip device in which the non-trip-free tripping means is omitted and the breaker trips free of the closing means each time the trip device functions. The invention is shown in Fig. 4 as applied to a circuit breaker of the type fully disclosed in the Patent No. 2,647,182, issued July 28, 1953 to Fritz E. Florschutz and Carl G. Lentjes. Since most of the parts of the circuit breaker shown in Fig. 4 are the same as those shown in Fig. 2, they are given the same reference numerals.

Referring to Fig. 4, the circuit breaker is held in the closed position by a latch 251 which engages a shoulder 253 on the coupling 27. The latch 251 is pivotally mounted on a pin 255 supported in the frame members 47 and is biased by means of a spring biased plunger 257 into latching engagement with the shoulder 253 on the coupling 27. The plunger 257 is slidably supported in an opening in a crossbar 261 supported between the frame members 47 and is biased by a compression spring 263 compressed between the crossbar 261 and a washer 265 on the plunger. The latch 251 is provided with a downwardly extending projection 267 which is adapted to be engaged by a projection 269 on the toggle link 33 to release the latch 251 upon operation of the trip device.

In addition to the light load latch 75 which is biased to the latched position by a spring 271, the trip device includes a tripping electromagnet indicated generally at 273 wh ch normally holds the latch 75 in latching position against the bias of the spring 271. The tripping electromagnet 273 is supported on the bracket 92 and comprises a pair of laminated magnet yoke members 275 having a permanent magnet 277 disposed between the lower ends thereof. The yoke members 275 are made in two parts, the upper part having recesses thereon for receiving a tripping coil 279. After the coil 279 is placed in the position shown, upper and lower portions of the yoke members 275 are suitably secured together as, for instance, by welding. The upper ends of the yokes 275 form pole faces which normally attract and hold an armature 281 which is pivotally connected to the latch 75 by a pin 283.

As long as the coil 279 is unenerg zed, the magnet 273 holds the armature 281 in the attracted position shown holding the latch 75 in latching position. When the coil 279 is energized by a tripping impulse, the area of the yoke members 275 adjacent the coil becomes saturated with flux and presents a h gh reluctance path between the permanent magnet and the armature. This reduces the flux through the armature 281 and causes the magnet 273 to release the armature 281 whereupon the force exerted on the toggle 71-73 moves the latch 75 to unlatching position against a stop 285 permitting collapse of the underset toggle 71-73. Collapse of the toggle 71-73 permits the main toggle 33-35 to collapse and the circuit breaker goes to the open position under the influence of the accelerating spring 13. As the main toggle 33-35 collapses, the toggle l nk 33 pivots clockwise on the pin 37 causing the projection 269 thereon to move the main latch 251 to unlatching position releasing the piston 23 which immediately is thrust upwardly by the spring 147 to effect resetting of the main toggle 33-35 to recouple the piston 23 to the breaker rod 31 in readiness for a closing operation. When the main toggle 33-35 is reset, the toggle link 73 is drawn toward the right resetting the tripping toggle 71-73 and permitting the spring 271 to reset the latch 75 and armature 281.

The circuit breaker is closed in the same manner as that described for the breaker shown in Figs. 1 and 2, that is, by admission of compressed gas to the cylinder 17 above the piston. This is accomplished by the identical inlet valve device shown in Figs. 1 and 3. As the breaker reaches the closed position, the main latch 251 is restored to its latching position to hold the breaker in the closed position.

The modification of the tripping magnet means shown in Fgs. 5 and 6 utilizes a single permanent magnet and a single energizing coil to control both the trip-free and non-trip-free latch means.

The tripping magnet indicated generally at 291 (Figs. 5 and 6) comprises a single permanent magnet 293 disposed between a pair of yokes 295. Mounted on the yokes 295 at the ends thereof are pairs of yoke members 297 and 298 each having a slot in the lower end thereof for receiving a single coil 299 common to both pairs of yoke members 297 and 298. Associated with each pair of yoke members 297 is an armature 301, one of which is pivotally connected to the non-trp-free latch carrier 78 and the other of which is pivotally connected to the tripfree latch 75. Each of the permanent magnet yokes 295 is provided with an outwardly extending pole piece 303 adjacent the yoke members 298. Each of the yoke members 298 is provided with an outwardly extending pole piece 305 spaced from the pole pieces 303. Disposed adjacent the pole p eces 303 and 305 are pieces 307 of magnetic material which are mounted on the arms 309 of a U-shaped lever 311 (Figs. 6 and 7). The lever 311 is pivoted by means of a pin 313 on a bracket 315 secured to the bracket 92. A spring 317 biases the lever 311 to the position shown in full lines in Fig. 7 in which the magnetic pieces 307 are adjacent the pole pieces 303 and 305.

As seen in the Fig. 7 modification, there is no magnetic pieces 307 provided adjacent the yoke members 295 and 297 for the non-trip-free latch 76, hence this latch will be actuated to unlatching position each time the common coil 299 is energized by a tripping impulse and the breaker will go to the open position non-trip-free of the operating piston. With the lever 311 in the position shown in Fig. 7, the magnetic pieces 307 are adjacent the pole pieces 303 and 305 on the trip-free yoke members 298. Consequently, the permanent magnet flux is bypassed around the area of saturation and the trip-free armature 301 holds the trip-free latch in latching position.

When compressed gas is admitted to the operating cylinder 17 to close the breaker, the piston 235 (Fig. l) acting through the piston rod 239 (Fig. 7) moves the lever 311 to the position 311a shown by dotted lines. This moves the magnetic pieces 307 away from the pole pieces 303 and 305 on the trip-free yoke members 298. Now, if the breaker closes against a fault the common trip coil 299 will be energized by the tripping impulse and the area of the yoke members 297 and 298 become saturated with flux presenting a high reluctance path between the permanent magnet and both of the armatures 301. This causes the yoke members 297 and 298 to release thier respective armatures 301 and permits simultaneous movement of both the trip-free latch 75 (Fig. 2) and the non-trip-free latch 76 to their unlatching positions. This permits collapse of the toggle 71-73 and simultaneously releases the latch 51 so that the breaker goes to the open position free of the operating piston and, at the same time, the spring 147 moves the operating piston 23 upwardly in the cylinder 17 to reset the tripping toggle 71-73 and recouple the piston to the breaker mechanism. High-speed retrieving is thus effected by simultaneously energizing the trip-free and non-trip-free tripping magnets.

While the invention has been disclosed in accordance with the provisions of the patent statutes, it is to be understood that various changes and modifications in the structural details may be made without departing from the spirit of the invention.

I claim as my invention:

1. A circuit breaker comprising relatively movable contacts and means releasable to effect opening of said contacts, power operated means for closing said contacts, trip-free tripping means and non-trip-free tripping means normally releasably restraining said releasable means in closed position and selectively operable to effect opening of said contacts, electroresponsive means operable when energized to effect energization of said power means, separate holding electromagnetic means normally releasably holding both of said tripping means in operative position, and operable when energized to selectively release said tripping means, magnetic trip selector means positioned relative to said separate electromagnetic holding means in response to the energized condition of said power means to selectively determine which of said holding electromagnetic means releases its associated tripping means.

2. A circuit breaker comprising relatively movable contacts and means releasable to effect opening of said contacts, power operated means for closing said contacts, trip-free tripping means and non-trip-free tripping means normally releasably restraining said releasable means in closed position and selectively operable to effect opening of said contacts, electroresponsive means operable when energized to effect energization of said power means, separate holding electromagnetic means normally releasably holding said tripping means in operative position and operable when energized to selectively release said tripping means, trip selector means operable in response to the energized condition of said power means to selectively determine which of said holding electromagnetic means releases its associated tripping means, and magnetic means on said trip selector positioned thereby relative to said holding electromagnets operable when said holding electromagnets are energized to cause the selected holding electromagnet to release its tripping means and cause the other holding electromagnet to restrain its tripping means.

3. A circuit breaker having relatively movable contacts and means releasable to effect opening of said contacts, power operated means for closing said contacts, trip-free tripping means and non-trip-free tripping means normally releasably restraining said releasable means in closed position and selectively operable to release said releasable means and effect opening of said contacts, electroresponsive means operable when energized to efiect energization of said power means, a pair of holding electromagnets normally releasably restraining said trip-free tripping means and said nontrip-free tripping means, said holding electromagnets being simultaneously energized in response to overload currents, and operable when energized to selectively release said tripping means, each of said holding electromagnets having portions which are saturated when said holding electromagnets are energized to efiect release of the associated tripping means, a trip selector positioned in response to the energized condition of said power means to select the holding electromagnet which is to efiect release of its tripping means, and magnetic means positioned by said trip selector relative to said holding electromagnets to efiect saturation of said electromagnets and cause it to release its associated tripping means and to prevent saturation of the other of said holding electromagnets and cause it to restrain its associated tripping means.

4. A circuit breaker having relatively movable contacts and means releasable to elfect opening of said contacts, power operated means for closing said contacts, trip-free tripping means and non-trip-free tripping means normally releasably restraining said releasable means in the closed position and selectively operable to effect release of said releasable means and opening of said contacts, electroresponsive means operable when energized to effect energization of said power means, a trip-free holding electro magnet and a non-trip-free holding electromagnet each having an armature connected to its associated tripping means normally releasably restraining said tripping means in operative position, said holding electromagnets being simultaneously energized in response to overload currents and operable when energized to selectively release its armature, each of said holding electromagnets having portions which are saturable when said holding electromagnets are energized to effect release of its armature and operation of its associated tripping means, a trip selector positioned in response to the energized condition of said power means to selectively cause saturation of said holding electromagnets, magnetic members on said trip selector, said trip selector when said power means is,

deenergized positioning said magnetic means adjacent the trip-free holding electromagnet to prevent saturation thereof and cause said trip-free tripping electromagnet to restrain the trip-free tripping means in operative position, and being positioned to permit saturation of said non-trip-free holding electromagnet and cause the latter to release the non-trip-free tripping means.

5. A circuit breaker comprising relatively movable contacts and operating mechanism releasable to efiect opening of said contacts, power operated means for closing said contacts, trip-free-tripping means and non-tripfree tripping means normally releasably restraining said operating mechanism in closed position and selectively releasable to etfect opening of said contacts, electroresponsive means operable when energized to effect energization of said power means, a trip-free holding electromagnet and a non-trip-free holding magnet normally releasably holding the related tripping means in operative position, said holding electromagnets when energized being operable by magnetic saturation to cause release of the associated tripping means, and a trip selector having magnetic means thereon and selectively positioned according to the energized condition of said power means to effect saturation of one of said holding electromagnets and prevent saturation of the other of said holding electromagnets.

References Cited in the file of this patent UNITED STATES PATENTS 

